Go to any Ron Paul event and it strikes you immediately. What's up with all the young people?

The 75-year-old Texas congressman packs halls on college campuses. His campaign volunteers often look too young to shave. And even at a recent New York City book signing, it was surprising to see how many teenagers and 20-somethings line up for an autograph clutching Paul's new book, Liberty Defined.

Sixteen-year-old Rob Gray says the age of the crowd doesn't seem odd to him.

It's "the old canard of the young being more open minded than the old," he says.

Paul, the world's most unlikely teen idol, is running again for president.